Strange FTP issue

["Jeff Crosby" <jlcrosby@xxxxxxxxxxxxxxxx>]

I _think_ this is a Windows issue, so I'm posting this here.

Our salesreps take orders via laptop.  These are sent in over a phone line
to a PC server in our office.  While they are still on the phone, the
order(s) are FTPed to the i5, processed, and the results FTPed back to that
PC server (all in batch).  Then those results are sent over the phone line
to the sales rep.  The laptop software and PC server front end are from a
third party.

Last week while I was 2000 miles away at DevCon I got a call that the orders
were going in to the i5 and being processed, but no results were getting
back to the salesrep laptops.  I VPNed in from Vegas and everything looked
just wonderful on the i5.  Being the Anal Retentive Individual that I am,
not only was I capturing the FTP log, but I was adding the FTP log to the
huge monster log file of everything going out to the salesreps.  This log on
the i5 would show:

 226 Transfer complete.
    557 bytes transferred in 0.003 seconds. Transfer rate 190.123 KB/sec.
 Enter an FTP subcommand.

Which, silly me, indicated the FTP transfer to the PC was working just fine,
thank you.  I called the vendor support for the third party.  They PC
Anywhered into this PC server and it showed receiving absolutely nothing
from the i5.  We were both stumped.

I finally called our IBM BP for suggestions what else to try/look for.  He
suggested trying to FTP to that PC server interactively and see what
happened.  I tried that and when I attempted to enter a user id in FTP, the
PC server responded that user could not sign on.  This made absolutely no
sense because that user id "access" is always signed on.  What I mean is
when that PC is booted, "access" is signed on automatically with password.
So I went to that PC to see if "access" was disabled or something.  No
problems with the user id.  Then, all of a sudden, a command-style looking
box popped up and hundreds of files names passed by.  Then it closed.  These
were all the files that had been FTPed to that PC server over a 2-day span.
They were then processed and the next time each salesrep called in, he/she
got all his/her results.  It's as if Windows was waiting for something, but
no one has any idea what.

Anyone have a clue what was going on?

Thanks.